Context switching costs in project heavy roles
Sequence project demand around the people shared between programmes. A portfolio can be feasible project by project and impossible in combination.
The performance question
A specialist assigned to several projects may spend the day rebuilding context and answering separate reporting requests. Look at simultaneous dependencies and conflicting delivery windows. The issue is the combined work design, not simply personal organisation.
What the evidence supports
Leroy’s experiments found attention residue when moving between tasks, and HSE recommends assessing workload across the whole team. The laboratory findings do not supply a cost per project switch or a safe maximum number of projects.[1][2]
A practical approach
Map shared specialists across the portfolio, including preparation and support work. Group related project tasks where feasible, agree one authoritative priority order and create clear handover notes for unavoidable switches. Change milestone timing if several projects need the same person’s intensive attention at once.
How to review progress
Review rework, stalled dependencies and the number of unplanned priority changes. Ask specialists which transitions require substantial reconstruction of context. Do not treat every change of task as harmful or multiply a generic switching figure by salary to claim savings.
Sources and references
- Attention residue when switching between work tasks Opens in a new tab
Sophie Leroy, Organizational Behavior and Human Decision Processes, 2009
Original research: abstract and two experimental studies
- Human factors: Workload Opens in a new tab
Health and Safety Executive
Processing limits, task analysis, workload drift and staffing